Radio wave band selector



April 17, 1934. I H, J KUNE 1,955,639

RADIO WAVE BAND SELECTOR Filed Dec. 19, 1952 Hdr/y Jffhhe.

INVENTOR ms ATTORNEYS Patented Apr. 17, 1934 UNITED STATES PATENT OFFICE This invention relates to certain novel improvements in radio wave band selectors, and has for its principal object the provision of an improved construction of this character which will be highly efiicient in use and economical in manufacture.

It is an object of this invention to provide a new and improved radio wave band selector.

Another object of the invention is to provide a new wave band selector by means of which the necessity, in the use of the prior art devices, for successively taking out and plugging in individual selector units or coils, when changing the reception from one wave band to another, is eliminated.

A further object of the invention is to provide an improved wave band selector having a series of selector coils and coil couples and fixed condensers associated with certain of the coils in such a manner that as a particular wave band selection is made tuning is also roughly accomplished for the particular wave band selected.

Other objects will appear hereinafter.

The invention consists in the novel combination and arrangement of parts to be hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawing, showing the preferred form of construction and in which:

Fig. 1 is a perspective view of a preferred form of the new selector;

Fig. 2 is a longitudinal sectional view on line 2-2 in Fig. 1;

Fig. 3 is a transverse sectional view on line 33 in Fig. 2;

Fig. 4 is a wiring diagram of the circuits embodied in the new selector; and

Fig. 5 is a perspective view of a modification of the new selector adapted for radio frequency amplification.

Fig. 6 is a view of a slightly modified form, in that it shows the use of fixed condensers shunted across the end windings of the coils of Fig. 4.

The new selector includes a non-conductive cylindrical core 10 and a base 11 which carries a group of prongs 23 that are attachable to an adapter or tube socket 24. Radially arranged on the base 11 are two stationary plate circuit contacts 12 and 13 and two stationary grid circuit contacts 14 and 15. These contacts as shown each have a yieldable or spring arm 16 and the core 10 is rotatably mounted on the base 11 between these spring arms 16.

Mounted on the core 10 in spaced relationship to each other is a series of coils 17, 18, 19, 20, 21 and 22. The end windings of these coils are electrically connected to an annular row or series of movable contacts 25 to 40, inclusive, mounted on the core 10 and adapted for wiping contact with the stationary contacts 12, 13, 14 and 15.

A fixed condenser 60 may be shunted across the end windings of the coils 18, 20, 21 and 22 as indicated in Fig. 6, for reasons to be set forth hereinafter, but these condensers are not necessary for the operation of the device as a wave band selector and may be dispensed with without departing from the purview of the invention and as shown in Fig. 4. However, by using these fixed condensers 60 tuning for the particular wave band selected is roughly accomplished when the wave band selection is made and the device is operated as hereinafter set forth.

The end windings of the plate circuit coil 1'? are electrically connected by conductors 41 and 42 to the movable contacts 30 and 26, respectively. The end windings of the grid coil 18 are electrically connected by conductors 43 and 44 to the movable contacts 34 and 38, respectively. Conductors 45 and 46 connect the end windings of the plate circuit coil 19 to the movable contacts 27 and 31, respectively. The end windings of the coil 20 are electrically connected by conductors 47 and 48 to the movable contacts 39 and 35, respectively. Conductors 49 and 50 connect the end windings of the coil 21 to the mov able contacts 36 and 40, respectively, while conductors 51 and 52 connect the end windings of the coil 22 to the movable contacts 37 and 25, respectively.

Leading from the movable contacts 35 and 36 to the movable contacts 28 and 29, respectively, are jumper conductors or wires 53 and 54, while leading from the movable contacts 39 and 40 to the movable contacts 32 and 33, respectively, are jumper conductors or wires 55 and 56.

Operation By positioning the core 10 so that the movable contacts 30 and 26 are engaged with the stationary plate circuit contacts 13 and 12, respectively, as in Fig. 4, the coils 17 and 18 act as a couple, in which the coil 17 is the primary or plate circuit coil, and the coil 18 is the secondary or grid circuit coil, since in this position of the core the movable contacts 34 and 38 are engaged with the stationary grid circuit contacts 14 and 15, respectively, while the movable contacts 30 and 26 are engaged with the stationary plate circuit contacts 13 and 12, respectively. Thus one end winding of the coil 17 is electrically connected to the plate circuit contact 13 by way can of conductor 42 and the other end winding of coil 17 is electrically connected to the other plate circuit contact 12 by way of conductor 41.

A fixed condenser 60 of suitable capacity may be shunted across the end windings of the grid coil 18 and when the selector is positioned for reception of a particular wave band, as in Fig. 4, the condenser 60 shunted across the end windings of the coil 18 automatically tunes the device roughly for reception in the selected band. This tuning must, of course, be supplemented by other controls for finer adjustment.

By rotating the core 10 and movable contacts thereon the distance between two of the movable contacts (clockwise, Fig. 4) the movable contacts 31 and 27 are engaged with the stationary plate circuit contacts 13 and 12, respectively; the movable contacts 39 and 35 are engaged with the stationary grid circuit contacts 15 and 14, respectively, and the coils 19 and 20 are thus coupled together and a particular wave band selected; the coil 19 then acting as the plate circuit or primary coil and the coil 20 acting as the grid circuit or secondary coil. In this position one end winding of the coil 19 is electrically connected to the stationary plate circuit contact 13 by way of conductor 46 and contact 31, while the other end winding of the coil 19 is electrically connected to the other plate circuit contact 12 by way of conductor and contact 27. At the same time one end winding of coil 20 is electrically connected to the stationary grid circuit contact 14 by way of conductor 48 and contact 35, while the other end winding of coil 20 is electrically connected to the other grid circuit contact 15 by way of conductor 47 and contact 39.

By rotating the core 10 and movable contacts thereon further clockwise (Fig. 4) the distance between two of the movable contacts, the movable contacts 32 and 28 are engaged with the two stationary plate circuit contacts 13 and 12, respectively; the movable contacts 36 and 40 are engaged with the stationary grid circuit contacts 14 and 15, respectively, and the coils 20 and 21 are thus coupled together. In this couple the coil 20 acts as the plate circuit or pri mary coil, since one end winding of the coil 20 is then electrically connected to the plate circuit contact 13 by way of the conductor 47, movable contact 39, jumper wire 55, and contact 32, while the other end winding of coil 20 is then electrically connected to the other stationary plate circuit contact 12 by way of conductor 48, contact 35, jumper wire 53 and contact 28. The polarity of the coil 20 is thus reversed and it becomes the primary or plate circuit coil of the coil couple 2021; while the coil 21 acts as the grid circuit or secondary coil. When this couple is in use the end windings of the coil 21 are electrically connected to stationary grid circuit contacts 14 and 15 as follows: One end winding of the coil 21 is electrically connected to the contact 14 by way of conductor 49 and contact 36, while the other end winding of coil 21 is then electrically connected to contact 15 by way of conductor 50 and contact 40.

By rotating the core 10 and movable contacts thereon still further (clockwise, Fig. 4) the distance between two of the movable contacts, the wave band represented by the coil couple 2122 may be selected. In this position of the parts one end winding of coil 21 is electrically connected to the stationary plate circuit contact 13 by way of conductor 50, jumper wire 56 and contact 33, while the other end Winding of coil 21 is electrically connected to the other stationary plate circuit contact 12 by way of conductor 49, contact 36, jumper wire 54 and contact 29. The polarity of the coil 21 is thus changed and it becomes the plate circuit or primary coil of the couple 2122. At the same time the coil 22 acts as the grid or secondary coil of the couple 2122, since one end winding of the grid coil 22 is then electrically connected to the stationary grid contact 14 by way of conductor 51 and contact 37, while the other end winding of the coil 22 is then electrically connected to the other stationary grid contact 15 by way of conductor 52 and contact 25.

It will thus be apparent to those skilled in the art that a particular wave band may be selected and the change from one band to another effected by simply rotating the core 10 the distance between two of the movable contacts thereon. The selector is not limited to the number of coils and coil couples shown as this number may be increased by increasing the number of coils and jumper wires.

In Fig. 5 two of the units shown in Figs. 1 to 4, inclusive, are generally indicated at 57 and r claim as new and desire to protect by Letters Patent is:

1. A radio wave band selector, comprising the combination of a stationary base, a core mounted for rotatable movement relative to the base, spaced coils on the core arranged in a series of grid and plate circuit couples, stationary grid and plate circuit contacts on the base, a row of movable contacts radially arran ed upon the core including contacts having the end windings of the coils directly connected thereto and adapted for engagement with the stationary plate and grid circuit contacts, said row including other movable contacts on the core, and jumper wires electrically connecting the last-named movable contacts with certain of the first-named movable contacts so as to change the polarity of certain of the coils in use from grid to plate circuit and conversely.

2. A radio wave band selector, comprising the combination of a stationary base, a core mounted for rotatable movement relative to the base, spaced coils on the core arranged in a series of grid and plate circuit couples, stationary grid and plate circuit contacts on the base, a row of movable contacts radially arranged upon the core including contacts having the end windings of the coils directly connected thereto and adapted for engagement with the stationary plate and grid circuit contacts, said row including other movable contacts on the core, jumper wires electrically connecting the last-named movable contacts with certain of the first-named movable contacts so as to change the polarity of certain of the coils in use from grid to plate circuit and conversely, and fixed condensers shunted across the end windings of certain of said coils.

3. A radio wave band selector, comprising the combination of abase and a core one movable relative to the other, coils wound about the core and arranged in a series of grid and plate circuit couples, grid and plate circuit contacts on the base, and a row of contacts radially arranged upon the core including contacts having the end windings of the coils directly connected thereto and adapted for engagement with the grid and plate circuit contacts, said row including other contacts, and jumper wires electrically connecting the said other and last-named contacts with certain other contacts in said row so as to change the polarity of certain of the coils in use from grid to plate circuit and conversely.

4. A radio wave band selector, comprising the combination of a base and a core one movable relative to the other, coils wound about the core and arranged in a series of grid and plate circuit couples, grid and plate circuit contacts on the base, a row of contacts radially arranged upon the core including contacts having the end windings of the coils directly connected thereto and adapted for engagement with the grid and plate circuit contacts, said row including other contacts, jumper wires electrically connecting the said other and last-named contacts with certain other contacts in said row so as to change the polarity of certain of the coils in use from grid to plate circuit and conversely, and fixed condensers shunted across the end windings of certain of said coils.

5. A radio wave band selector for radio frequency amplification circuits, comprising a rotatable shaft, cores fast on said shaft, a group of spaced coils on each of said cores and the said coils in each of said groups being arranged in a series of grid and plate circuit couples, a row of movable contacts radially arranged upon each of said cores including contacts having the end windings of said coils electrically connected thereto, a group of stationary grid and plate circuit contacts associated with each of said rows and adapted for engagement therewith, each of said rows including other contacts, and jumper wires associated with each of said rows electrically connecting the said other and last-named contacts therein with certain other contacts in said row so as to change the polarity of certain of said coils in use from grid to plate circuit and conversely.

6. A device of the character described, comprising the combination of: two parts, one movable relative to the other; a series of transformer coils arranged in couples upon one of said parts and a row of contact members arranged upon the other of said parts; and a row of contact memhers arranged upon the said first-named part for contacting engagement with the said first-named contact members; said second-named row including contact members having the end windings of certain of said coils electrically connected'thereto; said row including other contact members; and conductors electrically connecting the said other and last-named contact members with certain others of the said contact members in said secondnamed row so that certain of the said coils may be changed, in the use of the device, from primary to secondary and conversely thereof by moving one of said parts relative to the other.

7. A device of the character described, comprising the combination of: a series of transformer coils arranged in couples; two rows of contact members; the contact members in one of said rows being moxable relative to and in engagement with the contacts in the other of said rows; one of said rows including contact members having the end windings of certain of said coils electrically connected thereto; said one row including other contact members; and conductors electrically connecting the said other and last-named contact members with certain others of the said contact members in said one row so that in the use of the device certain of said coils may be changed from primary to secondary and conversely thereof by moving one of said rows of contact members relative to and in engagement with the other of said rows of contact members.

8. A device of the character described, comprising the combination of a rotatable shaft; groups of spaced coils arranged in transformer couples upon said shaft; a row of relatively movable contact members associated with each of said groups of coils and radially arranged upon said shaft for movement therewith; and a row of relatively stationary contact members associated with each of said groups of coils and arranged for engagement with the corresponding row of said movable contact members; each of said first-named rows of contact members includ ing contact members having the end windings of certain of said coils electrically connected thereto and each of said first-named rows including other contact members; and a group of conduct-ors associated with each of said first-named rows and electrically connecting the said other and last-named contact members with certain contact members in each of said first-named rows so that in the use of the device certain of said coils in each of said groups of coils may be changed from primary to secondary and conversely thereof.

HARRY J. KLINE. 

